scholarly journals Thymic regulation of hematopoiesis. III: Isolation of helper and suppressor populations using counterflow centrifugal elutriation

Blood ◽  
1986 ◽  
Vol 68 (3) ◽  
pp. 787-789
Author(s):  
SJ Sharkis ◽  
C Cremo ◽  
MI Collector ◽  
SJ Noga ◽  
AD Donnenberg
Keyword(s):  
Cell Types ◽  
Colony Growth ◽  
Minority Population ◽  
Intermediate Cell ◽  
Centrifugal Elutriation ◽  
Hematopoietic Progenitors ◽  
Majority Population ◽  
Helper Function ◽  
Positive And Negative Feedback

We have evidence that thymic regulatory cells can either enhance or inhibit the growth of hematopoietic progenitors in vitro. We have suggested that two separate populations are responsible for this regulatory interaction but isolation of the cell types has proven difficult. We now report the isolation by counterflow centrifugal elutriation (CCE) of two separate populations of thymocytes which regulate erythropoiesis in coculture. We demonstrate that a minority population (less than 10%) of slow sedimenting elutriated thymocytes provide a helper function whereas the suppressor population is the majority population. Furthermore, some thymocytes of intermediate cell volume neither enhance nor inhibit erythroid colony growth. We conclude that isolation of thymic subsets can lead to identification of populations which induce cell-cell regulation of hematopoietic progenitors resulting in both a positive and negative feedback control of growth.

scholarly journals Thymic regulation of hematopoiesis. III: Isolation of helper and suppressor populations using counterflow centrifugal elutriation

Blood ◽  
1986 ◽  
Vol 68 (3) ◽  
pp. 787-789 ◽  
Author(s):  
SJ Sharkis ◽  
C Cremo ◽  
MI Collector ◽  
SJ Noga ◽  
AD Donnenberg
Keyword(s):  
Cell Types ◽  
Colony Growth ◽  
Minority Population ◽  
Intermediate Cell ◽  
Centrifugal Elutriation ◽  
Hematopoietic Progenitors ◽  
Majority Population ◽  
Helper Function ◽  
Positive And Negative Feedback

Abstract We have evidence that thymic regulatory cells can either enhance or inhibit the growth of hematopoietic progenitors in vitro. We have suggested that two separate populations are responsible for this regulatory interaction but isolation of the cell types has proven difficult. We now report the isolation by counterflow centrifugal elutriation (CCE) of two separate populations of thymocytes which regulate erythropoiesis in coculture. We demonstrate that a minority population (less than 10%) of slow sedimenting elutriated thymocytes provide a helper function whereas the suppressor population is the majority population. Furthermore, some thymocytes of intermediate cell volume neither enhance nor inhibit erythroid colony growth. We conclude that isolation of thymic subsets can lead to identification of populations which induce cell-cell regulation of hematopoietic progenitors resulting in both a positive and negative feedback control of growth.

scholarly journals Collection of peripheral blood hematopoietic progenitors (PBHP) from patients with severe aplastic anemia (SAA) after prolonged administration of granulocyte colony-stimulating factor

Blood ◽  
1993 ◽  
Vol 82 (5) ◽  
pp. 1410-1414 ◽  
Author(s):  
A Bacigalupo ◽  
G Piaggio ◽  
M Podesta ◽  
MT Van Lint ◽  
M Valbonesi ◽  
...  
Keyword(s):  
Peripheral Blood ◽  
Autologous Transplantation ◽  
Colony Growth ◽  
Median Number ◽  
Granulocyte Colony Stimulating Factor ◽  
Colony Stimulating Factor ◽  
Hematopoietic Progenitors ◽  
Prolonged Administration ◽  
Stimulating Factor

Abstract The aim of this study was to test whether prolonged administration of granulocyte colony-stimulating factor (G-CSF) would allow the collection by leukapheresis of PBHP in patients with SAA. For this purpose, nine SAA patients, 7 to 46 years old, six of whom were enrolled at diagnosis of their disease and three after previous immunosuppression had failed, were treated with antilymphocyte globulin (ALG) (day 1 to 5), cyclosporin A (5 mg/kg/d orally) (day 6 to 90) and G-CSF 5 micrograms/kg/d (day 6 to 90). A total of 40 leukaphereses were performed, (range 2 to 7 per patient), between days +10 and +168 from G- CSF treatment. White blood cell count at the time of harvest ranged from 1.2 to 18.1 x 10(9)/L. Results can be summarized as follows: the median number of cells collected per patient was 5.0 x 10(8)/kg (range 2.6 to 18.7), the median number of CD34+ cells was 1.8 x 10(6)/kg (range 0.27 to 3.8) and the median number of colony-forming units granulocyte-macrophage (CFU-GM) was 3.9 x 10(4)/kg (range 0 to 39). Twenty leukaphereses performed between days +33 and +77 of G-CSF treatment grew granulocyte macrophages and erythroid colonies in vitro. No colony growth was obtained from 20 leukaphereses performed before day +33 or after day +80. In six patients the total number of CFU-GM recovered were in the range described for autologous peripheral blood stem cell grafts. (2.6 to 39 x 10(4)/kg). In conclusion, this study suggests that circulating hematopoietic progenitors can be recovered after ALG priming and after at least 1 month of G-CSF treatment in a proportion of patients with SAA. Whether these cells will be suitable for autologous transplantation remains to be determined.

scholarly journals Separation of helper T cells from suppressor T cells expressing different Ly components. I. Polyclonal activation: suppressor and helper activities are inherent properties of distinct T-cell subclasses.

1976 ◽  
Vol 143 (6) ◽  
pp. 1382-1390 ◽  
Author(s):  
J Jandinski ◽  
H Cantor ◽  
T Tadakuma ◽  
D L Peavy ◽  
C W Pierce
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cell Population ◽  
Cell Types ◽  
Target Cells ◽  
Con A ◽  
Suppressor Effect ◽  
Helper Function ◽  
Polyclonal Activator

Concanavalin A, a nonspecific polyclonal activator of T lymphocytes, activates Lyl and Ly23 subclasses to the same degree. After activation, the Ly23 subclass, but not the Lyl subclass, has the following properties: (a) Suppression of the antibody response to sheep erythrocytes (SRBC) in vitro. (b) Production of a soluble factor that suppresses the anti-SRBC response in vitro. (c) Suppression of the generation of cell-mediated cytotoxicity to H-2 target cells in vitro. Con A-activated cells of the Lyl subclass, but not the Ly23 subclass, express helper function in the anti-SRBC response in vitro. Because the intact Con A-stimulated T-cell population contains both cell types, these cells do not exert detectable helper effects in an anti-SRBC system in vitro, because the helper effect of Lyl cells is masked by the suppressor effect of the Ly23 cells. Each function is revealed by eliminating one or the other population with the relevant Ly antiserum. The resting T-cell population, before activation by Con A, also contains already programmed Lyl and Ly23 cells with similar helper and suppressor potentials, respectively. This is revealed by experiments with Ly subclasses which have been separated from the resting T-cell population and then stimulated by Con A. Thus helper and suppressor functions, as expressed in these systems, are manifestations of separate T-cell-differentiative pathways and do not depend upon stimulation of the cells by antigen.

scholarly journals Loss of proliferative capacity in immunohemopoietic stem cells caused by serial transplantation rather than aging.

1978 ◽  
Vol 147 (5) ◽  
pp. 1526-1531 ◽  
Author(s):  
D E Harrison ◽  
C M Astle ◽  
J A Delaittre
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Cell Lines ◽  
Cell Types ◽  
Colony Growth ◽  
Normal Function ◽  
Stem Cell Lines ◽  
Marrow Stem Cell ◽  
Serial Transplantation

Marrow stem cell lines from old donors and those from young controls gave equally rapid rates of colony growth on spleens of irradiated mice. Old and young stem cell lines competed equally well with chromosomally marked marrow stem cells from a young donor in producing cell types that are stimulated by bleeding; old cells competed 70% as well as young in producing cell types stimulated by phytohemagglutinin (PHA) in vitro. After a single serial transplantation, the rates of colony growth declined 1.5- to 2.5-fold, and the ability to compete declined 2- to 4-fold for bleeding-stimulated and 4- to 10-fold for PHA-stimulated cells. Thus, immediate stem cell proliferative capacities decline much more after one serial transplantation than after a lifetime of normal function.

scholarly journals Collection of peripheral blood hematopoietic progenitors (PBHP) from patients with severe aplastic anemia (SAA) after prolonged administration of granulocyte colony-stimulating factor

Blood ◽  
1993 ◽  
Vol 82 (5) ◽  
pp. 1410-1414
Author(s):  
A Bacigalupo ◽  
G Piaggio ◽  
M Podesta ◽  
MT Van Lint ◽  
M Valbonesi ◽  
...  
Keyword(s):  
Peripheral Blood ◽  
Autologous Transplantation ◽  
Colony Growth ◽  
Median Number ◽  
Granulocyte Colony Stimulating Factor ◽  
Colony Stimulating Factor ◽  
Hematopoietic Progenitors ◽  
Prolonged Administration ◽  
Stimulating Factor

The aim of this study was to test whether prolonged administration of granulocyte colony-stimulating factor (G-CSF) would allow the collection by leukapheresis of PBHP in patients with SAA. For this purpose, nine SAA patients, 7 to 46 years old, six of whom were enrolled at diagnosis of their disease and three after previous immunosuppression had failed, were treated with antilymphocyte globulin (ALG) (day 1 to 5), cyclosporin A (5 mg/kg/d orally) (day 6 to 90) and G-CSF 5 micrograms/kg/d (day 6 to 90). A total of 40 leukaphereses were performed, (range 2 to 7 per patient), between days +10 and +168 from G- CSF treatment. White blood cell count at the time of harvest ranged from 1.2 to 18.1 x 10(9)/L. Results can be summarized as follows: the median number of cells collected per patient was 5.0 x 10(8)/kg (range 2.6 to 18.7), the median number of CD34+ cells was 1.8 x 10(6)/kg (range 0.27 to 3.8) and the median number of colony-forming units granulocyte-macrophage (CFU-GM) was 3.9 x 10(4)/kg (range 0 to 39). Twenty leukaphereses performed between days +33 and +77 of G-CSF treatment grew granulocyte macrophages and erythroid colonies in vitro. No colony growth was obtained from 20 leukaphereses performed before day +33 or after day +80. In six patients the total number of CFU-GM recovered were in the range described for autologous peripheral blood stem cell grafts. (2.6 to 39 x 10(4)/kg). In conclusion, this study suggests that circulating hematopoietic progenitors can be recovered after ALG priming and after at least 1 month of G-CSF treatment in a proportion of patients with SAA. Whether these cells will be suitable for autologous transplantation remains to be determined.

scholarly journals Defining the variety of cell types in developing and adult human kidneys by single-cell RNA sequencing

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
A. Schumacher ◽  
M. B. Rookmaaker ◽  
J. A. Joles ◽  
R. Kramann ◽  
T. Q. Nguyen ◽  
...  
Keyword(s):  
Single Cell ◽  
Rna Sequencing ◽  
Renal Cell ◽  
Early Stage ◽  
Kidney Tissue ◽  
Cell Types ◽  
Intermediate Cell ◽  
Adult Human ◽  
Single Cell Rna Sequencing

AbstractThe kidney is among the most complex organs in terms of the variety of cell types. The cellular complexity of human kidneys is not fully unraveled and this challenge is further complicated by the existence of multiple progenitor pools and differentiation pathways. Researchers disagree on the variety of renal cell types due to a lack of research providing a comprehensive picture and the challenge to translate findings between species. To find an answer to the number of human renal cell types, we discuss research that used single-cell RNA sequencing on developing and adult human kidney tissue and compares these findings to the literature of the pre-single-cell RNA sequencing era. We find that these publications show major steps towards the discovery of novel cell types and intermediate cell stages as well as complex molecular signatures and lineage pathways throughout development. The variety of cell types remains variable in the single-cell literature, which is due to the limitations of the technique. Nevertheless, our analysis approaches an accumulated number of 41 identified cell populations of renal lineage and 32 of non-renal lineage in the adult kidney, and there is certainly much more to discover. There is still a need for a consensus on a variety of definitions and standards in single-cell RNA sequencing research, such as the definition of what is a cell type. Nevertheless, this early-stage research already proves to be of significant impact for both clinical and regenerative medicine, and shows potential to enhance the generation of sophisticated in vitro kidney tissue.

Ultrastructural Changes in Three Different Mammalian Cells Following Ultraviolet Laser Irradiation

1972 ◽  
Vol 30 ◽  
pp. 350-351
Author(s):  
K. Shankar Narayan ◽  
Kailash C. Gupta ◽  
Tohru Okigaki
Keyword(s):  
Ultraviolet Light ◽  
Mammalian Cells ◽  
Biological Effects ◽  
Survival Rates ◽  
Chinese Hamster ◽  
Cell Types ◽  
Differential Sensitivity ◽  
Ultrastructural Changes ◽  
Ultraviolet Laser

The biological effects of short-wave ultraviolet light has generally been described in terms of changes in cell growth or survival rates and production of chromosomal aberrations. Ultrastructural changes following exposure of cells to ultraviolet light, particularly at 265 nm, have not been reported.We have developed a means of irradiating populations of cells grown in vitro to a monochromatic ultraviolet laser beam at a wavelength of 265 nm based on the method of Johnson. The cell types studies were: i) WI-38, a human diploid fibroblast; ii) CMP, a human adenocarcinoma cell line; and iii) Don C-II, a Chinese hamster fibroblast cell strain. The cells were exposed either in situ or in suspension to the ultraviolet laser (UVL) beam. Irradiated cell populations were studied either "immediately" or following growth for 1-8 days after irradiation.Differential sensitivity, as measured by survival rates were observed in the three cell types studied. Pattern of ultrastructural changes were also different in the three cell types.

Ultrastructural observations on the in vitro cytoadherence of Plasmodium falciparum infected red blood cells

1990 ◽  
Vol 48 (3) ◽  
pp. 914-915
Author(s):  
D.J.P. Ferguson ◽  
A.R. Berendt ◽  
J. Tansey ◽  
K. Marsh ◽  
C.I. Newbold
Keyword(s):  
Plasmodium Falciparum ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Umbilical Vein ◽  
Cell Types ◽  
Amelanotic Melanoma ◽  
Cytoplasmic Process ◽  
Umbilical Vein Endothelial Cells

In human malaria, the most serious clinical manifestation is cerebral malaria (CM) due to infection with Plasmodium falciparum. The pathology of CM is thought to relate to the fact that red blood cells containing mature forms of the parasite (PRBC) cytoadhere or sequester to post capillary venules of various tissues including the brain. This in vivo phenomenon has been studied in vitro by examining the cytoadherence of PRBCs to various cell types and purified proteins. To date, three Ijiost receptor molecules have been identified; CD36, ICAM-1 and thrombospondin. The specific changes in the PRBC membrane which mediate cytoadherence are less well understood, but they include the sub-membranous deposition of electron-dense material resulting in surface deformations called knobs. Knobs were thought to be essential for cytoadherence, lput recent work has shown that certain knob-negative (K-) lines can cytoadhere. In the present study, we have used electron microscopy to re-examine the interactions between K+ PRBCs and both C32 amelanotic melanoma cells and human umbilical vein endothelial cells (HUVEC).We confirm previous data demonstrating that C32 cells possess numerous microvilli which adhere to the PRBC, mainly via the knobs (Fig. 1). In contrast, the HUVEC were relatively smooth and the PRBCs appeared partially flattened onto the cell surface (Fig. 2). Furthermore, many of the PRBCs exhibited an invagination of the limiting membrane in the attachment zone, often containing a cytoplasmic process from the endothelial cell (Fig. 2).

Role of the 807 C/T Polymorphism of the α2 Gene in Platelet GP Ia Collagen Receptor Expression and Function

1999 ◽  
Vol 81 (06) ◽  
pp. 951-956 ◽  
Author(s):  
J. Corral ◽  
R. González-Conejero ◽  
J. Rivera ◽  
F. Ortuño ◽  
P. Aparicio ◽  
...  
Keyword(s):  
Venous Thrombosis ◽  
Cell Types ◽  
Receptor Expression ◽  
Case Control Studies ◽  
Platelet Surface ◽  
Vitro Analysis ◽  
And Function ◽  
In Vitro Analysis

SummaryThe variability of the platelet GP Ia/IIa density has been associated with the 807 C/T polymorphism (Phe 224) of the GP Ia gene in American Caucasian population. We have investigated the genotype and allelic frequencies of this polymorphism in Spanish Caucasians. The T allele was found in 35% of the 284 blood donors analyzed. We confirmed in 159 healthy subjects a significant association between the 807 C/T polymorphism and the platelet GP Ia density. The T allele correlated with high number of GP Ia molecules on platelet surface. In addition, we observed a similar association of this polymorphism with the expression of this protein in other blood cell types. The platelet responsiveness to collagen was determined by “in vitro” analysis of the platelet activation and aggregation response. We found no significant differences in these functional platelet parameters according to the 807 C/T genotype. Finally, results from 3 case/control studies involving 302 consecutive patients (101 with coronary heart disease, 104 with cerebrovascular disease and 97 with deep venous thrombosis) determined that the 807 C/T polymorphism of the GP Ia gene does not represent a risk factor for arterial or venous thrombosis.

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